Method and apparatus for producing sheet glass



- Jail. 19, 1932.

J. L. DRAKE IETH O D AND AIPARATUS FOR PRODUCING SHEET GLASS I Filed larch '7, 1930 gwumuto'c Jbhn l .DraKe E IL Patented Jan. 19, 1932.

UNITED STATES PATENT orrlcs :omw a. run, or romeo, omo, ASBIGNQB. ro mnaY-oms-ronn emss comm,

or some, one, a conromrron or omo men an Arraauus son mnucme'smr-euss Application filed Ian-ch 1.1m. Serial mlcaaaio.

The present invention relates to a method and apparatus for producin sheet glass.

While this inventlon is 'prlmaril designed for use in connectionv with the Col urn rocsee for producing sheet glass, as exemp ified in Colburn Patent N 0. 1,248,809, granted December 4, 1917, it is of course not necessarily restricted to use in such connection as itcan well be adapted to other t es of sheet glass forming apparatus. In t e Oolburn process, however, the glass sheet is continuously drawn u wardly from a bath of molten glass contained in a suitable receptacle or draw-pot and after becoming substantially to set, although while still in a semi-plastic condition, isdeflected into a horizontal lane and passed horizontally through a com ined drawing and flattening mechanism intoan'd eer I through an annealing 90 An important object of the invention resides in the provision of a method and apparatus wherein the formation of surface defects or irregularities in the sheet will be reduced to a minimum so that a flatter, smoother, and more uniform thickness of sheet may be produced;

Another object of the inventi )n is the provision of a method and ap aratus for minimizing the formation of sur ace irregularities in the sheet durin the formation thereof by subjecting said s eat to a wiping or smoothing action at substantially the base or meniscus thereof.

A further ob'ect of the invention is the provision ofsuc a'method and apparatus as described above wherein the sheet may also, if desired, and during the deflecting thereof from the vertical to the horizontal, be

m dragged over suitable means producing a smoothing or flattening action upon the surface thereof.

Other objects and advantages of the invention will become more apparent during the 5 course of the following description when taken in connection with the accompanying drawings.

In the drawin wherein like numerals are employed to deslgnate like parts throughout to the same,

Fig. 1 is a vertical longitudinal section throu h sheet lass apparatus constructed in accor ance wit the present invention,

Fig. 2 is a side elevation of a portion there- I i 3 is an elevation showmg' 9. art of the s ructural details, and p ig. 4 is a sectional view of an alternative arrangement.

Referring now to the drawings, 5 designates a lass sheet continuously drawn upwardly From a mass of molten glass 6 contained in a suitable receptacle or draw-pot 7 and supplied thereto from any suitable type of furnace 8. The sheet 5 is drawn upwardly for a suitable distance and then, while still in a semilastic condition, isdeflected about the rotata le bending roll 9 into a substantially horizontal plane'as indicated at 5a, said sheet being then passed over a so-called idler roll 10 and draw table 11 into and through an annealing leer (not shown).

In the Colburn process as ordinarily practiced, suitable knurled rollers or other width maintaining means are positioned to engage if opposite edges of the sheet at the base thereof to prevent narrowing of the sheet as itis drawn upwardly. However, in accordance with the present invention, the usual sheet edge engaging means are omitted and there are substituted therefor the preferably metallic members 12 and 13 which extend the entire width of the sheet and are adapted to engage opposite surfaces thereof at the base or meniscus 14. These members are in the form of hollow, substantially rectangular casings and are provided not only to maintain the sheet to width, but also to minimize the formation of surface defects or irregularities in said sheet as it is being formed. Thus, these members produce a wiping action upon opposite surfaces of the glass as it is drawn upwardly therebetween and thereby have a tendency to flatten or smooth out the glass so as to minimize the formation of surface irregularities in the sheet as it is being formed whereby to aid in producing a flatter, and smoother sheet of a more uniform thicksees.

2 aseaove The members 12 and 13 are preferably su ported slightly above but closely adjacent t e molten bath 6, and the inner adjacent side walls 15 and 16 of said members are arcuately curved transversely as shown, with the lower portions thereof fitting substantially into the curvature of the sheet meniscus 14. The members are adapted to be internally cooled by the circulation of a suitable temperature control medium therethrough and the said members, or at least those portions contacting with the glass, are preferably constructed from a suitable non-corrosive material such as nickel, nichrome, monel, or the like, which will take and retain a high polish.

Although not absolutely essential to the present invention, it may be desirable at times to omit the usual rotatable bending roll.

9 and to substitute therefor a stationary member such as is illustrated in Fig. 4 and designated 17. This member is also in the form of a hollow, substantially rectangular casing but is provided at one of its corners with a laterally offset portion 18 over which the sheet is deflected from the vertical to the horizontal. This member is likewise adapted to have circulated therethrough a suitable temperature control medium and the entire member or just that portion in contact with the glass may be constructed of a non-corrosive material. As the sheet is deflected from the vertical to the horizontal, it will be dragged over the member 17 and this draggmg action will efiect the smoothing or flattenm out of the sheet.

In i 3 is illustrated one way in which the mem ers 12 and 13 may be mounted. As shown, these members are provided at opposite ends with the hollow tubular extensions 19 and '20 respectively, the extension 19 at each end of member 12 being carried by a support 21 fixedly secured to a base member 22, while the extension 20 at each end of member 13 is carried by a support 23 slidably mounted upon said base member and normally urged toward the first member'by a compression. spring 24. The compression springs 24 at opposite ends of member 13 are provlded to normally urge said member in- In sheet glass ap aratus, means for draw-' ing a sheet upward y from a bath of molten glass, stationary members engaging opposite surfaces of the sheet at the base or meniscus thereof and having a wiping or smoothing action thereon, and means for yieldably urging one of said members toward the other.

bigned at Toledo, in the county of Lucas and State of Ohio, this 5th day of March,

JOHN L. DRAKE.

wardly toward member 12, but are of such a 7 nature that the members can be readily moved apart to permit the passage of clay or other foreign matter therebetween and in this manner prevent injury to the highly polished surfaces thereof. member 13 is limited, however, by the adj ustment of nut 25 u support 23 at eac end of said member and pxassmg outwardly through the respective ed bracket 27. The tubular extensions 19 and 20 facilitate the introduction of the coollng medium into the members 12 and 13 and its subsequent discharge therefrom.

It is to be understood that the form of the n bolt 26 carried by the The inward movement of 

